1 /*- 2 * Copyright (c) 2014, 2015 The FreeBSD Foundation. 3 * Copyright (c) 2014 Andrew Turner. 4 * All rights reserved. 5 * 6 * This software was developed by Andrew Turner under 7 * sponsorship from the FreeBSD Foundation. 8 * 9 * Portions of this software were developed by Konstantin Belousov 10 * under sponsorship from the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/kernel.h> 39 #include <sys/systm.h> 40 #include <sys/exec.h> 41 #include <sys/imgact.h> 42 #include <sys/linker.h> 43 #include <sys/proc.h> 44 #include <sys/reg.h> 45 #include <sys/sysent.h> 46 #include <sys/imgact_elf.h> 47 #include <sys/syscall.h> 48 #include <sys/signalvar.h> 49 #include <sys/vnode.h> 50 51 #include <vm/vm.h> 52 #include <vm/vm_param.h> 53 54 #include <machine/elf.h> 55 #include <machine/md_var.h> 56 57 #include "linker_if.h" 58 59 u_long __read_frequently elf_hwcap; 60 u_long __read_frequently elf_hwcap2; 61 62 struct arm64_addr_mask elf64_addr_mask; 63 64 static struct sysentvec elf64_freebsd_sysvec = { 65 .sv_size = SYS_MAXSYSCALL, 66 .sv_table = sysent, 67 .sv_fixup = __elfN(freebsd_fixup), 68 .sv_sendsig = sendsig, 69 .sv_sigcode = sigcode, 70 .sv_szsigcode = &szsigcode, 71 .sv_name = "FreeBSD ELF64", 72 .sv_coredump = __elfN(coredump), 73 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 74 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 75 .sv_elf_core_prepare_notes = __elfN(prepare_notes), 76 .sv_imgact_try = NULL, 77 .sv_minsigstksz = MINSIGSTKSZ, 78 .sv_minuser = VM_MIN_ADDRESS, 79 .sv_maxuser = VM_MAXUSER_ADDRESS, 80 .sv_usrstack = USRSTACK, 81 .sv_psstrings = PS_STRINGS, 82 .sv_psstringssz = sizeof(struct ps_strings), 83 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 84 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs), 85 .sv_copyout_strings = exec_copyout_strings, 86 .sv_setregs = exec_setregs, 87 .sv_fixlimit = NULL, 88 .sv_maxssiz = NULL, 89 .sv_flags = SV_SHP | SV_TIMEKEEP | SV_ABI_FREEBSD | SV_LP64 | 90 SV_ASLR | SV_RNG_SEED_VER, 91 .sv_set_syscall_retval = cpu_set_syscall_retval, 92 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 93 .sv_syscallnames = syscallnames, 94 .sv_shared_page_base = SHAREDPAGE, 95 .sv_shared_page_len = PAGE_SIZE, 96 .sv_schedtail = NULL, 97 .sv_thread_detach = NULL, 98 .sv_trap = NULL, 99 .sv_hwcap = &elf_hwcap, 100 .sv_hwcap2 = &elf_hwcap2, 101 .sv_onexec_old = exec_onexec_old, 102 .sv_onexit = exit_onexit, 103 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 104 .sv_regset_end = SET_LIMIT(__elfN(regset)), 105 }; 106 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec); 107 108 static Elf64_Brandinfo freebsd_brand_info = { 109 .brand = ELFOSABI_FREEBSD, 110 .machine = EM_AARCH64, 111 .compat_3_brand = "FreeBSD", 112 .emul_path = NULL, 113 .interp_path = "/libexec/ld-elf.so.1", 114 .sysvec = &elf64_freebsd_sysvec, 115 .interp_newpath = NULL, 116 .brand_note = &elf64_freebsd_brandnote, 117 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 118 }; 119 120 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 121 (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_info); 122 123 static bool 124 get_arm64_addr_mask(struct regset *rs, struct thread *td, void *buf, 125 size_t *sizep) 126 { 127 if (buf != NULL) { 128 KASSERT(*sizep == sizeof(elf64_addr_mask), 129 ("%s: invalid size", __func__)); 130 memcpy(buf, &elf64_addr_mask, sizeof(elf64_addr_mask)); 131 } 132 *sizep = sizeof(elf64_addr_mask); 133 134 return (true); 135 } 136 137 static struct regset regset_arm64_addr_mask = { 138 .note = NT_ARM_ADDR_MASK, 139 .size = sizeof(struct arm64_addr_mask), 140 .get = get_arm64_addr_mask, 141 }; 142 ELF_REGSET(regset_arm64_addr_mask); 143 144 void 145 elf64_dump_thread(struct thread *td __unused, void *dst __unused, 146 size_t *off __unused) 147 { 148 } 149 150 bool 151 elf_is_ifunc_reloc(Elf_Size r_info __unused) 152 { 153 154 return (ELF_R_TYPE(r_info) == R_AARCH64_IRELATIVE); 155 } 156 157 static int 158 reloc_instr_imm(Elf32_Addr *where, Elf_Addr val, u_int msb, u_int lsb) 159 { 160 161 /* Check bounds: upper bits must be all ones or all zeros. */ 162 if ((uint64_t)((int64_t)val >> (msb + 1)) + 1 > 1) 163 return (-1); 164 val >>= lsb; 165 val &= (1 << (msb - lsb + 1)) - 1; 166 *where |= (Elf32_Addr)val; 167 return (0); 168 } 169 170 /* 171 * Process a relocation. Support for some static relocations is required 172 * in order for the -zifunc-noplt optimization to work. 173 */ 174 static int 175 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 176 int type, int flags, elf_lookup_fn lookup) 177 { 178 #define ARM64_ELF_RELOC_LOCAL (1 << 0) 179 #define ARM64_ELF_RELOC_LATE_IFUNC (1 << 1) 180 Elf_Addr *where, addr, addend, val; 181 Elf_Word rtype, symidx; 182 const Elf_Rel *rel; 183 const Elf_Rela *rela; 184 int error; 185 186 switch (type) { 187 case ELF_RELOC_REL: 188 rel = (const Elf_Rel *)data; 189 where = (Elf_Addr *) (relocbase + rel->r_offset); 190 addend = *where; 191 rtype = ELF_R_TYPE(rel->r_info); 192 symidx = ELF_R_SYM(rel->r_info); 193 break; 194 case ELF_RELOC_RELA: 195 rela = (const Elf_Rela *)data; 196 where = (Elf_Addr *) (relocbase + rela->r_offset); 197 addend = rela->r_addend; 198 rtype = ELF_R_TYPE(rela->r_info); 199 symidx = ELF_R_SYM(rela->r_info); 200 break; 201 default: 202 panic("unknown reloc type %d\n", type); 203 } 204 205 if ((flags & ARM64_ELF_RELOC_LATE_IFUNC) != 0) { 206 KASSERT(type == ELF_RELOC_RELA, 207 ("Only RELA ifunc relocations are supported")); 208 if (rtype != R_AARCH64_IRELATIVE) 209 return (0); 210 } 211 212 if ((flags & ARM64_ELF_RELOC_LOCAL) != 0) { 213 if (rtype == R_AARCH64_RELATIVE) 214 *where = elf_relocaddr(lf, relocbase + addend); 215 return (0); 216 } 217 218 error = 0; 219 switch (rtype) { 220 case R_AARCH64_NONE: 221 case R_AARCH64_RELATIVE: 222 break; 223 case R_AARCH64_TSTBR14: 224 error = lookup(lf, symidx, 1, &addr); 225 if (error != 0) 226 return (-1); 227 error = reloc_instr_imm((Elf32_Addr *)where, 228 addr + addend - (Elf_Addr)where, 15, 2); 229 break; 230 case R_AARCH64_CONDBR19: 231 error = lookup(lf, symidx, 1, &addr); 232 if (error != 0) 233 return (-1); 234 error = reloc_instr_imm((Elf32_Addr *)where, 235 addr + addend - (Elf_Addr)where, 20, 2); 236 break; 237 case R_AARCH64_JUMP26: 238 case R_AARCH64_CALL26: 239 error = lookup(lf, symidx, 1, &addr); 240 if (error != 0) 241 return (-1); 242 error = reloc_instr_imm((Elf32_Addr *)where, 243 addr + addend - (Elf_Addr)where, 27, 2); 244 break; 245 case R_AARCH64_ABS64: 246 case R_AARCH64_GLOB_DAT: 247 case R_AARCH64_JUMP_SLOT: 248 error = lookup(lf, symidx, 1, &addr); 249 if (error != 0) 250 return (-1); 251 *where = addr + addend; 252 break; 253 case R_AARCH64_IRELATIVE: 254 addr = relocbase + addend; 255 val = ((Elf64_Addr (*)(void))addr)(); 256 if (*where != val) 257 *where = val; 258 break; 259 default: 260 printf("kldload: unexpected relocation type %d, " 261 "symbol index %d\n", rtype, symidx); 262 return (-1); 263 } 264 return (error); 265 } 266 267 int 268 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 269 int type, elf_lookup_fn lookup) 270 { 271 272 return (elf_reloc_internal(lf, relocbase, data, type, 273 ARM64_ELF_RELOC_LOCAL, lookup)); 274 } 275 276 /* Process one elf relocation with addend. */ 277 int 278 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 279 elf_lookup_fn lookup) 280 { 281 282 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 283 } 284 285 int 286 elf_reloc_late(linker_file_t lf, Elf_Addr relocbase, const void *data, 287 int type, elf_lookup_fn lookup) 288 { 289 290 return (elf_reloc_internal(lf, relocbase, data, type, 291 ARM64_ELF_RELOC_LATE_IFUNC, lookup)); 292 } 293 294 int 295 elf_cpu_load_file(linker_file_t lf) 296 { 297 298 if (lf->id != 1) 299 cpu_icache_sync_range((vm_offset_t)lf->address, lf->size); 300 return (0); 301 } 302 303 int 304 elf_cpu_unload_file(linker_file_t lf __unused) 305 { 306 307 return (0); 308 } 309 310 int 311 elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused) 312 { 313 314 return (0); 315 } 316